Left ventricular mechanics in late second trimester of healthy pregnancy

Peripartum Cardiomyopathy: A Case Series Emphasizing the Significance of Left Ventricular Global Longitudinal Strain Imaging

Peripartum cardiomyopathy (PPCM) poses diagnostic and management challenges, while left ventricular global longitudinal strain (LV GLS) provides crucial insights into myocardial function. This case series explores the significance of LV GLS imaging in diagnosing and managing PPCM. Three distinct cases of varying severity highlight the significance of LV-GLS in assessing myocardial function during the peripartum period. Each case exhibited varying degrees of cardiac impairment, with LV GLS serving as a sensitive indicator of dysfunction. Treatment response, closely monitored through LV GLS changes, emphasizes the importance of this imaging technique in evaluating therapy efficacy. The discussion underscores deviations from traditional management approaches, emphasizing the need for personalized strategies in PPCM. Nonetheless, the study's limitations stress the need for broader research to validate these findings across diverse populations and settings, as well as long-term follow-up of the patients who had persistence of abnormal global longitudinal strain values despite recovery of left ventricular ejection fraction.

Evaluation of left ventricular function of pregnant women with autoimmune diseases using speckle tracking echocardiography

Pregnancy can cause fluctuations in autoimmune diseases (AD) women, which may aggravate the cardiac damage. Maternal heart function is very important for maternal and fetal health. Therefore, early and accurate evaluation of the heart function of AD pregnant women is necessary. This study was aimed to evaluate the left ventricular (LV) function of AD pregnant women using two-dimensional speckle tracking echocardiography (2DSTE). A total of 96 subjects, including 26 non-pregnant AD patients (AD group), 33 AD pregnant women (AD-P group), and 37 healthy pregnant women (H-P group) were conducted. Baseline clinical and conventional echocardiography characteristics of all the subjects were collected. The 2DSTE was performed to acquire layer-specific strain parameters of LV. Compared with H-P group, AD-P group showed no significant differences in GLSmid and GLSepi. However, the GLSendo (24.10 [22.30 to 25.40] vs. 21.70 [19.05 to 25.15], P = 0.023) and ΔGLS (5.50 [4.80 to 6.00] vs. 4.90 [4.20 to 5.80], P = 0.017) were decreased, while the PSD (27 [23 to 32] vs. 32 [24 to 44], P = 0.014) was increased. At the segmental level, there was no significant difference in apex LSmid and LSepi between the two groups, while the AD-P group showed transmural dysfunction in basal and middle segments, and the LSendo in apex segments (32.84 [28.34 to 34.25] vs. 27.97 [21.87 to 33.61], P = 0.021) were significantly decreased. Compared with AD group, AD-P group showed no significant difference in ΔGLS, PSD, and GLS parameters of three layers. For the segmental level, there were no significant differences in the LSepi of the apex segment and the LS in three layers of the basal and middle segments between the two groups, while LSendo (32.69 [29.13 to 35.53] vs. 27.97 [21.87 to 33.60], P = 0.017) and LSmid (24.70 [22.24 to 27.78] vs. 21.32 [16.91 to 26.11], P = 0.023) in apex segments were significantly lower in AD-P group. The anti-SSA/Ro antibody were positive independently correlated with PSD. In conclusion, layer-specific strain parameters and PSD by 2DSTE provide an accurate and reproducible measurement of myocardial function. There are subclinical LV myocardial dysfunction in AD pregnant women. Besides, the positive of anti-SSA/Ro antibody maybe associated with LV myocardial dysfunction.

Transthoracic Echocardiographic Assessment of the Heart in Pregnancy-a position statement on behalf of the British Society of Echocardiography and the United Kingdom Maternal Cardiology Society

Pregnancy is a dynamic process associated with profound hormonally mediated haemodynamic changes which result in structural and functional adaptations in the cardiovascular system. An understanding of the myocardial adaptations is important for echocardiographers and clinicians undertaking or interpreting echocardiograms on pregnant and post-partum women. This guideline, on behalf of the British Society of Echocardiography and United Kingdom Maternal Cardiology Society, reviews the expected echocardiographic findings in normal pregnancy and in different cardiac disease states, as well as echocardiographic signs of decompensation. It aims to lay out a structure for echocardiographic scanning and surveillance during and after pregnancy as well as suggesting practical advice on scanning pregnant women.

Usefulness of second trimester left ventricular global longitudinal strain for predicting adverse maternal outcome in pregnant women aged 35 years or older

The present study was primarily designed to accurately determine biventricular and biatrial myocardial function, assessed by two-dimensional speckle tracking echocardiography (2D-STE), in a prospective cohort of pregnant women aged ≥ 35 years, at the second trimester of pregnancy. Secondly, we aimed at investigating the main independent predictors of adverse maternal outcome (AMO) in the same study population. 80 consecutive pregnant women aged ≥ 35 years, 80 gestational week-matched (18.4 ± 1.6 vs 18.5 ± 1.8 weeks, p = 0.71) pregnant women aged < 35 years and 80 non-pregnant women aged ≥ 35 years without any comorbidity were included in this prospective study. All pregnant women underwent obstetric evaluation, modified Haller index (MHI) assessment and a conventional two-dimensional transthoracic echocardiography implemented with complete 2D-STE analysis of both ventricles and atria at the second trimester of pregnancy. AMO was defined as the occurrence of any of the following: gestational hypertension (GH) including preeclampsia; gestational diabetes mellitus (GDM); preterm delivery (PD); emergency caesarean section (ECS); postpartum haemorrhage (PPH); premature rupture of membranes (PROM); maternal death. Compared to younger pregnant women, pregnant women aged ≥ 35 years were more likely to be found with: (1) body mass index (BMI) ≥ 30 kg/m2 (37.5% of total); (2) significantly increased inflammatory markers; (3) significantly greater left ventricular mass index; (4) significantly impaired hemodynamics; (5) significantly reduced bi-atrial and bi-ventricular myocardial strain parameters, despite normal ejection fraction. A strong inverse correlation between second trimester BMI and left ventricular (LV)-global longitudinal strain (GLS) (r =  - 0.84) and between second trimester MHI and LV-GLS (r =  - 0.81) was demonstrated in pregnant women aged ≥ 35 years. GH, GDM, PD, ECS, PPH and PROM were detected in 15%, 12.5%, 10%, 8.7%, 8.7% and 7.5% of women, respectively. Age (OR 2.04, 95% CI 1.46-2.84), second trimester BMI (OR 2.40, 95% CI 1.64-3.51) and second trimester LV-GLS (OR 0.07, 95%C I 0.01-0.34) were independently associated with outcome. Age ≥ 37 years, BMI ≥ 30 kg/m2 and LV-GLS less negative than - 18% were the best cut-off values for predicting AMO. A LV-GLS less negative than - 18% allows to identify, among older pregnant women, those with an increased risk of AMO. Both intrinsic myocardial dysfunction and extrinsic compressive mechanical phenomena might affect global myocardial deformation during gestation.

Chest conformation spuriously influences strain parameters of myocardial contractile function in healthy pregnant women

AIMS

Left ventricular (LV) contractility during noncomplicated pregnancy has been previously investigated by two-dimensional speckle-tracking echocardiography (2D-STE), with conflicting results. Chest abnormalities might affect myocardial strain parameters, yet this issue has not been previously investigated during pregnancy. We evaluated the influence of chest conformation on myocardial strain parameters in healthy pregnant women.

METHODS

Between October 2019 and February 2020, 50 healthy pregnant women (32.3 ± 4.0 years old) were consecutively studied. They underwent obstetric visit, assessment of chest shape by modified Haller index (MHI; chest transverse diameter over the distance between sternum and spine) and transthoracic echocardiography implemented with 2D-STE analysis of all myocardial strain parameters in the first trimester (12-14 weeks), third trimester (36-38 weeks) and 6-9 weeks after delivery.

RESULTS

LV ejection fraction remained substantially unchanged (P = 0.13), while on the average all myocardial strain parameters showed a small but significant decrease during pregnancy, and recovered postpartum (all P < 0.001). Women with concave-shaped chest wall (MHI > 2.5, n = 29), and those with normal chest conformation (MHI ≤ 2.5, n = 21) were then separately analyzed. Pregnant women with MHI above 2.5, but not those with MHI 2.5 or less, showed a progressive but reversible decrease in all myocardial strain parameters (all P < 0.001). MHI was strongly correlated with LV global longitudinal strain (r = -0.87) and LV global circumferential strain (r = -0.83) in the third trimester of pregnancy.

CONCLUSION

Myocardial strain impairment during healthy pregnancy may not reflect intrinsic myocardial dysfunction but rather intraventricular dyssynchrony related to a narrow antero-posterior chest diameter and rise in the diaphragm, with consequent extrinsic myocardial compression.

Cardiac Responses to Prenatal Resistance Exercise with and without the Valsalva Maneuver

PURPOSE

Exercise guidelines recommend incorporating resistance exercise (RE) into a regular aerobic training program during pregnancy. However, few women do so because of uncertainties about the safety of prenatal RE, particularly regarding the Valsalva maneuver (VM). The aim of this study was to determine the acute cardiovascular responses to prenatal RE at different intensities, with and without VM.

METHODS

Healthy pregnant (n = 15; 22.9 ± 5.9 wk of gestation) and nonpregnant women (n = 15) were recruited. Maximal strength over 10 repetitions (10RM) for semireclined leg press was determined. Women underwent standardized assessments of cardiac structure, function and mechanics (echocardiography), heart rate (ECG), and blood pressure (photoplethysmography) at baseline, during RE at 20%, 40%, and 60% 10RM while free-breathing, and at 40% 10RM with VM. Significant differences were identified between subjects at baseline (independent t-tests), between and within subjects during free-breathing RE (general linear model, baseline as a covariate), and between and within subjects for 40% 10RM free-breathing versus VM (mixed-effects model).

RESULTS

Resting cardiac output, heart rate, and stroke volume were greater in pregnant women, without differences in blood pressure, ejection fraction, or cardiac mechanics. During free-breathing RE, pregnant women had a greater ejection fraction compared with nonpregnant women; however, all other hemodynamic variables were not different between groups. Cardiac mechanics during free-breathing RE across all intensities were not different between groups, with the exception that pregnant women had a lower apical circumferential strain that did not affect global cardiac function. No differences were observed between groups during 40% 10RM RE with and without VM.

CONCLUSIONS

Pregnant women have proportionate cardiac responses to light-moderate RE, both with and without the VM. These findings reinforce the safety of RE in healthy pregnancy.

Prenatal Exercise and Cardiovascular Health (PEACH) Study: Impact on Muscle Sympathetic Nerve (Re)Activity

PURPOSE

Women who develop gestational hypertension have evidence of elevated muscle sympathetic nerve activity (MSNA) in early pregnancy, which continues to rise after diagnosis. Exercise has been shown to play a preventative role in the development of gestational hypertension and has been shown to reduce resting and reflex MSNA in nonpregnant populations. We sought to investigate whether aerobic exercise affected the sympathetic regulation of blood pressure between the second and third trimesters of pregnancy.

METHODS

We conducted a randomized controlled trial of structured aerobic exercise (n = 31) compared with no intervention (control, n = 28) beginning at 16-20 wk and continuing until 34-36 wk of gestation (NCT02948439). Women in the exercise group were prescribed aerobic activity at 50%-70% of their heart rate reserve, on 3-4 d·wk-1 for 25-40 min with a 5-min warm-up and 5-min cool-down (i.e., up to 160 min total activity per week). At preintervention and postintervention assessments, data from ~10 min of quiet rest and a 3-min cold pressor test were analyzed to determine sympathetic nervous system activity and reactivity.

RESULTS

MSNA was obtained in 51% of assessments. Resting MSNA burst frequency and burst incidence increased across gestation (main effect of gestational age, P = 0.002). Neurovascular transduction was blunted in the control group (P = 0.024) but not in exercisers (P = 0.873) at the postintervention time point. Lastly, MSNA reactivity during the cold pressor test was not affected by gestational age or exercise (P = 0.790, interaction).

CONCLUSIONS

These data show that exercise attenuates both the rise in MSNA and the blunting of neurovascular transduction. This may partially explain the lower risk of developing gestational hypertension in women who are active during their pregnancies.

Persistence of abnormal global longitudinal strain in women with peripartum cardiomyopathy

OBJECTIVES

Data regarding the longitudinal relationship of global longitudinal strain (GLS) and echocardiographic parameters are lacking in peripartum cardiomyopathy (PPCM). We evaluated GLS and its correlation with change (∆) in left ventricular ejection fraction (LVEF).

METHODS

We retrospectively identified women age ≥16 years hospitalized at Montefiore Medical Center in Bronx, NY from 1999-2015 with International Statistical Classification of Diseases and Related Health Problems, 9th revision codes for PPCM or an occurrence of unexplained heart failure during or up to 5 months postpartum. N = 195 charts were reviewed for inclusion/exclusion criteria, n = 53 patients met criteria for PPCM, and of those, n = 13 had a baseline and follow-up echocardiogram suitable for GLS analysis.

RESULTS

Of those eligible for strain analysis, the mean age was 30 ± 6 years, 46.2% identified as Black and 38.5% as Hispanic/Latina. Baseline LVEF was 30 (25, 35)%, GLS was -13.2 (-14, -7.6)%. At a mean follow-up time of 1.2 ± 0.7 years, 11/13 had persistently mild -15.6 (-16.3, -12.7)%, and 2/13 severely abnormal GLS -7.05 (-7.1, -7.0)%. There was no correlation between baseline GLS and ∆LVEF (r = .014, P = .965).

CONCLUSIONS

Global longitudinal strain is a sensitive method to identify subclinical myocardial dysfunction. In this series of women with PPCM, GLS remained persistently abnormal over time, even if LVEF improved. Future studies should examine the implication of persistently abnormal GLS in PPCM.

Adaptation of left ventricular diastolic function to pregnancy: a systematic review and meta-analysis

Objective:

To meta-analytically determine the adaptation of left ventricular diastolic function (LVDF)-indices to singleton normotensive pregnancies.

Methods:

Literature was retrieved from PubMed and Embase. We included studies that reported a nonpregnant reference measurement and LVDF indices (mitral inflow signals, left atrial volume and tissue Doppler measurements). Mean differences between pregnant and reference measurements and weighted means of absolute values were calculated using a random-effects model.

Results:

We included 34 eligible studies. Normotensive pregnancies were characterized by an initially larger increase in the passive left ventricular filling (E-wave peak velocity, 13%) compared to active left ventricular filling during diastole (A-wave peak velocity, 6%) resulting in a 16% increase of the E/A ratio in the first trimester. The E/A ratio progressively decreased during advancing gestation to −18% at term, resulting from stabilizing E-wave peak velocity and increased A-wave peak velocity. The E/e′ ratio was increased between 22 and 35 weeks (a maximal increase of 13%) in normotensive pregnancy. Left atrial volume (LAV) progressively increased from 15 weeks onwards with a maximal increase of 30% between 36 and 41 weeks.

Conclusion:

LVDF in normotensive pregnancy was improved in the first trimester after which LVDF progressively worsened. Large-scale studies in normotensive and hypertensive complicated pregnancies are needed for a more precise insight into LVDF changes during pregnancy.

Cardiac Responses to Submaximal Isometric Contraction and Aerobic Exercise in Healthy Pregnancy

PURPOSE

The increased physiological demand of pregnancy results in the profound adaptation of the maternal cardiovascular system, reflected by greater resting cardiac output and left ventricular (LV) deformation. Whether the increased resting demand alters acute cardiac responses to exercise in healthy pregnant women is not well understood.

METHODS

Healthy nonpregnant (n = 18), pregnant (n = 14, 22-26 wk gestation), and postpartum women (n = 13, 12-16 wk postdelivery) underwent assessments of cardiac function and LV mechanics at rest, during a sustained isometric forearm contraction (30% maximum), and during low-intensity (LOW) and moderate-intensity (MOD) dynamic cycling exercise (25% and 50% peak power output). Significant differences (α = 0.05) were determined using ANCOVA and general linear model (resting value included as covariate).

RESULTS

When accounting for higher resting cardiac output in pregnant women, pregnant women had greater cardiac output during isometric contraction (2.0 ± 0.3 L·min-1·m-1.83; nonpregnant, 1.3 ± 0.2 L·min-1·m-1.83; postpartum, 1.5 ± 0.5 L·min-1·m-1.83; P = 0.02) but similar values during dynamic cycling exercise (pregnant, LOW = 2.8 ± 0.4 L·min-1·m-1.83, MOD = 3.4 ± 0.7 L·min-1·m-1.83; nonpregnant, LOW = 2.4 ± 0.3 L·min-1·m-1.83, MOD = 3.0 ± 0.3 L·min-1·m-1.83; postpartum, LOW = 2.3 ± 0.4 L·min-1·m-1.83, MOD = 3.0 ± 0.5 L·min-1·m-1.83; P = 0.96). Basal circumferential strain was higher in pregnant women at rest, during the sustained isometric forearm contraction (-23.5% ± 1.2%; nonpregnant, -14.6% ± 1.4%; P = 0.001), and during dynamic cycling exercise (LOW = -27.0% ± 4.9%, MOD = -27.4% ± 4.6%; nonpregnant, LOW = -15.8% ± 4.5%, MOD = -15.2% ± 6.7%; P = 0.012); however, other parameters of LV mechanics were not different between groups.

CONCLUSION

The results support that the maternal heart can appropriately respond to additional cardiac demand and altered loading experienced during acute isometric and dynamic exercise, although subtle differences in responses to these challenges were observed. In addition, the LV mechanics that underpin global cardiac function are greater in pregnant women during exercise, leading to the speculation that the hormonal milieu of pregnancy influences regional deformation.

Cardiovascular function during triplet pregnancy

Pregnancy is recognized as a natural physiological stressor to the maternal cardiovascular system. Cardiovascular adaptation is markedly greater in twin pregnancy compared with singleton pregnancy; however, these changes are sparsely documented in triplet pregnancy. The aim of this case series was to compare maternal cardiac function, cardioautonomic regulation, and blood pressure reactivity in healthy singleton, twin, and triplet pregnancies. Resting cardiac structure and function (echocardiography), beat-by-beat blood pressure variability (BPV; photoplethysmography), and heart rate variability (HRV; electrocardiogram) were measured in two triplet, three twin, and three singleton pregnancies (matched for maternal age, prepregnancy body mass index, and gestational age). Hemodynamic responses to a 3-min cold pressor test were also recorded to assess blood pressure reactivity. Due to the small sample size of this case series, statistical comparisons were not made between groups. Compared with singleton and twin pregnancies, individuals pregnant with triplets had greater resting cardiac output but lower cardiac deformation (longitudinal strain, basal circumferential strain, and torsion), sympathetic dominance in cardioautonomic regulation (lower HRV and higher BPV), and elevated blood pressure reactivity in response to the cold pressor test. Taken together, these observations suggest that females with triplet pregnancies may have reduced cardiovascular function, which may contribute to the heightened risk of complications in multifetal pregnancies.NEW & NOTEWORTHY Individuals with healthy triplet pregnancies had greater resting cardiac output but lower left ventricular mechanics when compared with singleton and twin pregnancies matched for gestational age. In addition, triplet pregnancies had greater blood pressure variability and lower overall heart rate variability compared with singleton pregnancies, as well as greater blood pressure reactivity to the cold pressor test. Healthy triplet pregnancies may have reduced cardiovascular function as well as a greater sympathetic contribution to cardiac control.